WeatherGeek

Back when I was a weather geek during the early Mesozoic, we used to hand analyze these charts and hang them on the wall. Now you can get them on your iPhone and loop them (WeatherGeek Pro is available in App store here). Of course, you don't need to spend $4.99 to check out these freely available NWS computer-generated products. They have been available here for years (the site is moving to a newer flash-based version here that likely won't work with iPhone).